Problem I have been struggling with

I am new to this forum and I really could use some help if any one has the answer please let me know how you got it

The magnitudes FA=40 N and FB=50 N FC=40 N

the angles alpha=50 deg and beta = 80 degrees

Determine the magnitude of FA+FB+FC

The book has the answer as 83 N and I have not clue on how they got this answer.

Can anyone help

1 Attachment(s)

OK here is the clearification for the question posted

OK attached to the link is the question I have 2.3 and 2.6 . I am having a hard time setting up the problem. Please click on the question link

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